Squeeze bottles are used to package and dispense various kinds of products. Such a bottle is made of elastically deformable plastic, and when manually squeezed to dispense its contents, resiliently springs back to its original shape upon release of the squeeze pressure. This permits the bottle to be made with a predetermined shape which except while the bottle is squeezed, is retained throughout the useful life of the bottle. The bottle shape is used to identify the source of the bottled product and to appeal to the aesthetic sense of the user.
When such a squeeze bottle is used to package and dispense viscous products, exemplified by viscous hair shampoos and detergents, mustard, ketchup, etc., its mouth has been provided with a manually operated valve arrangement because the more convenient dispensing valves of prior art construction cannot handle viscous products. A dispensing valve opens and closes automatically dependent on the pressure of a liquid product controlled by the valve.
For the merchandizing of viscous products packaged in squeeze bottles, millions of the bottles may be involved. Manufacturing cost per bottle is important. If the bottle is to be provided with a dispensing valve, the valve must not only be effective so it recloses adequately tightly after the bottle is squeezed, but it also must be made of as few parts as possible with the parts capable of production at low cost and involving the least possible assembly cost. Preferably like the bottle itself, the parts should be capable of being made of plastic. The valve must provide for venting the bottle so that after the bottle is released from squeeze pressure it can spring back with reasonable promptness to its original shape through its elastic recovery properties, by permitting the bottle to suck in air to replace the product squeezed from the bottle.
One example of a possible squeeze bottle valve is provided by the Mancusi Jr. Pat. No. 3,206,079, Sept. 14, 1965. As stated by this patent, the construction it discloses represents a determined effort to provide a simplified dispensing valve which vents after product-dispensing is released. However, this patented valve construction involves the use of three parts which must be separately manufactured, the bottle mouth itself forming a necessary fourth part, and the valve action is effected by flexing a spring disk or diaphragm having inner and outer peripheries which seat on annular valve seats. To handle viscous products, the product would have to be squeezed from between the disk and seal by the spring-back of the disk to effect a closure, and the spring disk cannot provide any large force for this purpose.
Although unfitted for use with a squeeze bottle which must spring back to its original shape repeatedly, the Nilson Pat. No. 3,981,419, Sept. 21, 1976, does disclose a simple valve made of two plastic parts, an outer part being elastically deformable outwardly when receiving the force of a pressurized product, this outer part unsealing a valve head formed by an inner part. However, in this case also, an annular valve seat is involved, and if this patented construction is to be used to handle a viscous product, closing action is uncertain because of the need for the valve to squeeze the product from between annular surfaces when the valve-opening product pressure is released. No container venting action is provided.
Insofar as is known, the prior art has not provided a squeeze bottle having a dispensing valve capable of handling viscous products, which is of simple construction permitting low-cost manufacture and assembly in large quantities, which automatically opens and closes when the squeeze bottle is squeezed and released, and which when closed, positively seals the squeeze bottle contents against loss when the bottle having the valve is tilted or inverted either during shipment or use, and having a construction permitting the incorporation of a check valve for venting the bottle and which can be made as an integral part of the valve.